For the Sauce:
Rehydrate soy curls according to package directions. Once rehydrated, squeeze out all excess water.
In saucepan, combine soy sauce, water, sugar, garlic, ginger, and red pepper flakes. Bring to boil. Combine cornstarch and water to make a slurry, add to sauce and continue to cook over medium heat until thickened (if sauce gets too thick just add a little more water). Keep warm.
Heat oil over medium/high heat in large sauté pan or wok. Add soy curls and stir fry until starting to brown. Add scallions and continue to cook until soy curls are golden and scallions softened.
Add sauce and toss to combine.
Serve with rice and garnish with sesame seeds, if desired.